remove net/zlib.c (use -lz now)

export NO_NET and SA_ZLIB to the Makefile (from Makefile.inc)
add -p printf flag (tiny code) just for gcc -Wall
import latest alloc.c from netbsd
text    data    bss     dec     hex
400     8       0       408     198

1 files changed, 137 insertions, 19 deletions

diff --git a/sys/lib/libsa/alloc.c b/sys/lib/libsa/alloc.c
index 785b4a77d73..d985a1930fe 100644
--- a/sys/lib/libsa/alloc.c
+++ b/sys/lib/libsa/alloc.c
@@ -1,7 +1,10 @@
-/*	$OpenBSD: alloc.c,v 1.3 1996/12/08 15:15:45 niklas Exp $	*/
-/*	$NetBSD: alloc.c,v 1.4 1996/09/26 23:15:00 cgd Exp $	*/
+/*	$OpenBSD: alloc.c,v 1.4 1997/02/06 14:22:33 mickey Exp $	*/
+/*	$NetBSD: alloc.c,v 1.6 1997/02/04 18:36:33 thorpej Exp $	*/
 
-/*-
+/*
+ * Copyright (c) 1997 Christopher G. Demetriou.  All rights reserved.
+ * Copyright (c) 1996
+ *	Matthias Drochner.  All rights reserved.
  * Copyright (c) 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -65,46 +68,161 @@
  * rights to redistribute these changes.
  */
 
+/*
+ * Dynamic memory allocator.
+ *
+ * Compile options:
+ *
+ *	ALLOC_TRACE	enable tracing of allocations/deallocations
+ *
+ *	ALLOC_FIRST_FIT	use a first-fit allocation algorithm, rather than
+ *			the default best-fit algorithm.
+ *
+ *	HEAP_LIMIT	heap limit address (defaults to "no limit").
+ *
+ *	HEAP_START	start address of heap (defaults to '&end').
+ *
+ *	DEBUG		enable debugging sanity checks.
+ */
+
 #include <sys/param.h>
 
 /*
- *	Dynamic memory allocator
+ * Each block actually has ALIGN(unsigned) + ALIGN(size) bytes allocated
+ * to it, as follows:
+ *
+ * 0 ... (sizeof(unsigned) - 1)
+ *	allocated or unallocated: holds size of user-data part of block.
+ *
+ * sizeof(unsigned) ... (ALIGN(sizeof(unsigned)) - 1)
+ *	allocated: unused
+ *	unallocated: depends on packing of struct fl
+ *
+ * ALIGN(sizeof(unsigned)) ... (ALIGN(sizeof(unsigned)) + ALIGN(data size) - 1)
+ *	allocated: user data
+ *	unallocated: depends on packing of struct fl
+ *
+ * 'next' is only used when the block is unallocated (i.e. on the free list).
+ * However, note that ALIGN(sizeof(unsigned)) + ALIGN(data size) must
+ * be at least 'sizeof(struct fl)', so that blocks can be used as structures
+ * when on the free list.
  */
+
+#include "stand.h"
+
 struct fl {
-	struct fl	*next;
 	unsigned	size;
+	struct fl	*next;
 } *freelist = (struct fl *)0;
 
+#ifdef HEAP_START
+static char *top = (char*)HEAP_START;
+#else
 extern char end[];
 static char *top = end;
+#endif
 
 void *
 alloc(size)
 	unsigned size;
 {
-	register struct fl *f = freelist, **prev;
+	register struct fl **f = &freelist, **bestf = NULL;
+	unsigned bestsize = 0xffffffff;	/* greater than any real size */
+	char *help;
+	int failed;
 
-	prev = &freelist;
-	while (f && f->size < size) {
-		prev = &f->next;
-		f = f->next;
+#ifdef ALLOC_TRACE
+	printf("alloc(%u)", size);
+#endif
+
+#ifdef ALLOC_FIRST_FIT
+	while (*f != (struct fl *)0 && (*f)->size < size)
+		f = &((*f)->next);
+	bestf = f;
+	failed = (*bestf == (struct fl *)0);
+#else
+	/* scan freelist */
+	while (*f) {
+		if ((*f)->size >= size) {
+			if ((*f)->size == size) /* exact match */
+				goto found;
+
+			if ((*f)->size < bestsize) {
+				/* keep best fit */
+	                        bestf = f;
+	                        bestsize = (*f)->size;
+	                }
+	        }
+	        f = &((*f)->next);
 	}
-	if (f == (struct fl *)0) {
-		f = (struct fl *)ALIGN(top);
-		top = (char *)f + ALIGN(size);
-	} else
-		*prev = f->next;
-	return ((void *)f);
+
+	/* no match in freelist if bestsize unchanged */
+	failed = (bestsize == 0xffffffff);
+#endif
+
+	if (failed) { /* nothing found */
+	        /*
+		 * allocate from heap, keep chunk len in
+		 * first word
+		 */
+	        help = top;
+
+		/* make _sure_ the region can hold a struct fl. */
+		if (size < ALIGN(sizeof (struct fl *)))
+			size = ALIGN(sizeof (struct fl *));
+		top += ALIGN(sizeof(unsigned)) + ALIGN(size);
+#ifdef HEAP_LIMIT
+		if (top > (char*)HEAP_LIMIT)
+		        panic("heap full (0x%lx+%u)", help, size);
+#endif
+		*(unsigned *)help = ALIGN(size);
+#ifdef ALLOC_TRACE
+		printf("=%p\n", help + ALIGN(sizeof(unsigned)));
+#endif
+		return(help + ALIGN(sizeof(unsigned)));
+	}
+
+	/* we take the best fit */
+	f = bestf;
+
+found:
+        /* remove from freelist */
+        help = (char*)*f;
+	*f = (*f)->next;
+#ifdef ALLOC_TRACE
+	printf("=%p (origsize %u)\n", help + ALIGN(sizeof(unsigned)),
+	    *(unsigned *)help);
+#endif
+	return(help + ALIGN(sizeof(unsigned)));
 }
 
 void
 free(ptr, size)
 	void *ptr;
-	unsigned size;
+	unsigned size; /* only for consistence check */
 {
-	register struct fl *f = (struct fl *)ptr;
+	register struct fl *f =
+	    (struct fl *)((char*)ptr - ALIGN(sizeof(unsigned)));
+#ifdef ALLOC_TRACE
+	printf("free(%p, %u) (origsize %u)\n", ptr, size, f->size);
+#endif
+#ifdef DEBUG
+        if (size > f->size)
+	        printf("free %u bytes @%p, should be <=%u\n",
+		    size, ptr, f->size);
+#ifdef HEAP_START
+	if (ptr < (void *)HEAP_START)
+#else
+	if (ptr < (void *)end)
+#endif
+		printf("free: %lx before start of heap.\n", (u_long)ptr);
 
-	f->size = ALIGN(size);
+#ifdef HEAP_LIMIT
+	if (ptr > (void *)HEAP_LIMIT)
+		printf("free: %lx beyond end of heap.\n", (u_long)ptr);
+#endif
+#endif /* DEBUG */
+	/* put into freelist */
 	f->next = freelist;
 	freelist = f;
 }